Re: [PATCH v3 0/3] firewire: assist unit driver to compute packet time stamp

[Takashi Sakamoto <o-takashi@sakamocchi.jp>]

On Thu, Apr 07, 2022 at 08:02:10AM +0200, Takashi Iwai wrote:
> On Thu, 07 Apr 2022 02:10:21 +0200,
> Takashi Sakamoto wrote:
> > 
> > On Tue, Apr 05, 2022 at 06:23:35PM +0200, Takashi Iwai wrote:
> > > On Tue, 05 Apr 2022 09:22:18 +0200,
> > > Takashi Sakamoto wrote:
> > > > 
> > > > Hi,
> > > > 
> > > > Current implementation of Linux FireWire subsystem doesn't allow unit
> > > > driver to operate content of packet in IR context according to
> > > > time stamp. Additionally it doesn't allow unit driver to read current value
> > > > of CYCLE_TIME register in OHCI 1394 controller. It brings disadvantages to
> > > > drivers in Linux sound subsystem in regards of handling time for sampled
> > > > data such as PCM frames and MIDI messages.
> > > > 
> > > > This rerolled patchset is first step to improve the situation.
> > > > 
> > > > Changes in v3:
> > > >  * Rebase v2 patchset to v5.18-rc1
> > > > Changes in v2:
> > > >  * Rebase v1 patchset to v5.16 release
> > > >  * https://lore.kernel.org/lkml/20220212022131.199855-1-o-takashi@sakamocchi.jp/
> > > > V1:
> > > >  * https://lore.kernel.org/lkml/20211202113457.24011-1-o-takashi@sakamocchi.jp/
> > > > 
> > > > Hector Martin (1):
> > > >   firewire: Add dummy read_csr/write_csr functions
> > > > 
> > > > Takashi Sakamoto (2):
> > > >   firewire: add kernel API to access CYCLE_TIME register
> > > >   firewire: add kernel API to access packet structure in request
> > > >     structure for AR context
> > > 
> > > Thanks, applied all three patches now to for-next branch.
> > 
> > Although thanks for your applying them into your tree, I apologize to
> > trouble you if you overlook that the included changes is just for Linux
> > FireWire subsystem. It's my fault to send them only to Linux sound
> > subsystem, but the changes are required to my work in sound drivers... 
> > 
> > If you are willing to include patches to Linux FireWire subsystem for
> > your pull-request to Linus, I can prepare respined patches for it since
> > I have the list of patches posted to LKML as bug fixes for Linux FireWire
> > subsystem.
> > 
> > I need any help to solve current situation of Linux FireWire subsystem
> > that bug fixes and new changes are hardly merged. Of course, IEEE 1394 bus
> > is already outdated and legacy, but I know that some users still work
> > with it. If your path is available for it, it's the easiest and the most
> > convenient way for upstreaming, I think.
> 
> Ah OK, it's fine for me in either way.  I can keep up those changes in
> my tree, or go through others.  I leave the decision Firewire
> subsystem people.  Just let me know.

That's great. I think we can see few objections.

In this weekend, I'll send two respined patchset. One is for bug fixes for
your for-linus and living stables. Another is for your linux-next.

Thanks for your kindness.


Takashi Sakamoto